Supersaturated Solutions Using Crystallization Enthalpy to Impact Temperature Change to Wet Wipes

ABSTRACT

Personal care products comprising supersaturated solutions and core compositions comprising activation means are disclosed. In one embodiment, a core composition comprising the activation means is surrounded by an encapsulation layer. The core composition comprising the activation means may be introduced into wet wipes such that, upon rupture and contact between the supersaturated solution and the activation means, the wet wipe solution is warmed resulting in a warm sensation on a user&#39;s skin. Any number of other active ingredients, such as biocides, can also be incorporated into the personal care product.

BACKGROUND OF THE DISCLOSURE

The present disclosure relates generally to products incorporatingcompositions including supersaturated solutions capable of imparting atemperature change to the products through crystallization enthalpy.More particularly, the present disclosure is directed to supersaturatedsolutions that can be effectively utilized in a wipe or similar productsuch that, upon use and activation, the supersaturated solutions arecontacted with one or more activation means, which causes a warmingsensation on the skin upon product use. The products may include one ormore other active ingredients.

Wet wipes and dry wipes and related products have been used for sometime by consumers for various cleaning and wiping tasks. For example,many parents have utilized wet wipes to clean the skin of infants andtoddlers before and after urination and/or defecation. Many types of wetwipes are currently commercially available for this purpose.

Today, many consumers are demanding that personal health care products,such as wet wipes, have the ability to not only provide their intendedcleaning function, but also to deliver a comfort benefit to the user. Inrecent studies, it has been shown that baby wet wipes currently on themarket are sometimes perceived to be uncomfortably cold upon applicationto the skin, particularly for newborns. To mitigate this problem, therehave been many attempts to produce warming products to warm the wipes tocomfort the wet wipe users from the inherent “chill” given off by thecontact of the moistened wipes upon the skin.

These warming products are generally electrically operated and come intwo distinct styles. One is an “electric blanket” style which is sizedto wrap around the external surfaces of a plastic wet wipes container.The other is a self-contained plastic “appliance” style which warms thewet wipes with its internally positioned heating element. Though suchcurrently known and available wet wipe warming products typicallyachieve their primary objective of warming the wet wipe prior to use,they possess certain deficiencies, which can detract from their overallutility and desirability.

Perhaps the biggest deficiency of the current wet wipe warming productsis their inability to sustain the moisture content of the wet wipes.More specifically, drying of the wet wipes occurs due to heating oftheir moisture which accelerates dehydration. As a result, wet wipes maybecome dried-out and unusable.

Other complaints by wipe warmer users include discoloration of the wetwipes after heating, which appears to be inevitable because of areaction of various chemicals in the wipes upon the application of heat.Wipe warmer users further complain about warmer inconvenience andpotential electrical fire hazards, which can result with the use ofelectrical warming products.

Based on the foregoing, there is a need in the art for wet wipes thatcan produce a warming sensation just prior to, or at the point of use,without using external heating products. It would be desirable if thewet wipes could produce a warming sensation within less than about 10seconds after activation and raise the temperature of the wet wipesolution and the wet wipe base substrate at least 20° C. or more for atleast 20 seconds.

SUMMARY OF THE DISCLOSURE

The present disclosure relates to supersaturated solutions andactivation means, suitable for use in personal care products, such aswet wipes, dry wipes, cloths, and the like. Other active agents may alsobe employed in the personal care products, such as biocide agents.

In one embodiment, the supersaturated solution, upon contact with anactivation means in a wet wipe, for example, can produce a warmingsensation on the skin when the wet wipe is used. The supersaturatedsolution is typically incorporated into a composition and the activationmeans is typically incorporated into a separate core composition.Optionally, the core composition may also include a matrix material, asurfactant and a wax material surrounding the activation means toimprove overall performance. Additionally, the core composition andcomponents therein are optionally encapsulated in a thin capsule thatmay have one or more moisture protective layers and/or fugitive layersthereon to impart additional advantageous characteristics. Upon use in awet wipe, the core composition containing the activation means isbrought into contact with the supersaturated solution present in the wetwipe and releases heat to cause a warming sensation on the skin.

As such, the present disclosure is directed to a wet wipe comprising acomposition comprising a supersaturated solution, and a core compositionsurrounded by an encapsulation layer. The core composition comprises amatrix material and an activation means.

The present disclosure is further directed to a wet wipe comprising agelled composition comprising a supersaturated solution and a gellingagent, and a core composition surrounded by an encapsulation layer. Thecore composition comprises a matrix material and an activation means.

The present disclosure is further directed to a wet wipe comprising abasesheet material, a first fluid-impermeable pouch comprising acomposition comprising a supersaturated solution, and a secondfluid-impermeable pouch comprising a core composition comprising anactivation means.

The present disclosure is further directed to a wet wipe comprising afibrous sheet material. The fibrous sheet material comprises acomposition comprising a supersaturated solution, and a core compositionsurrounded by an encapsulation layer. The core composition comprises amatrix material and an activation means.

The present disclosure is further directed to a method of producing awipe. The method comprises encapsulating an activation means within acore composition; and incorporating a composition comprising asupersaturated solution, and the core composition within a basesheetmaterial.

Other features of the present disclosure will be in part apparent and inpart pointed out hereinafter.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A is a side view of a wet wipe comprising a supersaturatedsolution and an activation means being incorporated into a fibrous sheetmaterial and further being entrapped between two film layers asdisclosed in one embodiment of the present disclosure.

FIG. 1B is a top view of the fibrous sheet material including thesupersaturated solution and activation means of the wet wipe depicted inFIG. 1A.

FIG. 2A is a side view of a wet wipe comprising a gelled compositioncomprising a supersaturated solution and an activation means beingentrapped between two film layers as disclosed in one embodiment of thepresent disclosure.

FIG. 2B is a top view of the gelled composition including thesupersaturated solution and activation means of the wet wipe depicted inFIG. 2A.

FIG. 3A is a side view of a wet wipe comprising a gelled compositioncomprising a supersaturated solution, and a powdered activation meansdispersed in a pouch, wherein the gelled composition is separated fromthe activation means by air as disclosed in one embodiment of thepresent disclosure.

FIG. 3B is an end view of the pouch containing the gelled compositionand the activation means of the wet wipe depicted in FIG. 3A.

FIG. 4A is a side view of a wet wipe comprising a supersaturatedsolution being incorporated into two separate pouches and a powderedactivation means dispersed in a strip between the two pouches asdisclosed in one embodiment of the present disclosure.

FIG. 4B is an end view of the pouches containing the supersaturatedsolution and the strip including the activation means of the wet wipedepicted in FIG. 4A.

DEFINITIONS

Within the context of this specification, each term or phrase below willinclude, but not be limited to, the following meaning or meanings:

-   -   (a) “Bonded” refers to the joining, adhering, connecting,        attaching, or the like, of two elements. Two elements will be        considered to be bonded together when they are bonded directly        to one another or indirectly to one another, such as when each        is directly bonded to intermediate elements.    -   (b) “Film” refers to a thermoplastic film made using a film        extrusion and/or forming process, such as a cast film or blown        film extrusion process. The term includes apertured films, slit        films, and other porous films which constitute liquid transfer        films, as well as films which do not transfer liquid.    -   (c) “Layer” when used in the singular can have the dual meaning        of a single element or a plurality of elements.    -   (d) “Meltblown” refers to fibers formed by extruding a molten        thermoplastic material through a plurality of fine, usually        circular, die capillaries as molten threads or filaments into        converging high velocity heated gas (e.g., air) streams which        attenuate the filaments of molten thermoplastic material to        reduce their diameter, which may be to microfiber diameter.        Thereafter, the meltblown fibers are carried by the high        velocity gas stream and are deposited on a collecting surface to        form a web of randomly dispersed meltblown fibers. Such a        process is disclosed for example, in U.S. Pat. No. 3,849,241 to        Butin et al. (Nov. 19, 1974). Meltblown fibers are microfibers        which may be continuous or discontinuous, are generally smaller        than about 0.6 denier, and are generally self bonding when        deposited onto a collecting surface. Meltblown fibers used in        the present disclosure are preferably substantially continuous        in length.    -   (e) “Nonwoven” refers to materials and webs of material which        are formed without the aid of a textile weaving or knitting        process.    -   (f) “Polymeric” includes, but is not limited to, homopolymers,        copolymers, such as for example, block, graft, random and        alternating copolymers, terpolymers, etc. and blends and        modifications thereof. Furthermore, unless otherwise        specifically limited, the term “polymeric” shall include all        possible geometrical configurations of the material. These        configurations include, but are not limited to, isotactic,        syndiotactic and atactic symmetries.    -   (g) “Thermoplastic” describes a material that softens when        exposed to heat and which substantially returns to a nonsoftened        condition when cooled to room temperature.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present disclosure relates to compositions including supersaturatedsolutions, suitable for use in personal care products such as wet wipesand dry wipes. The present disclosure also relates to self warming wipesthat include a supersaturated solution and one or more activation means.The supersaturated solution, upon activation and contact with anactivation means, is capable of evolving heat and causing a warmingsensation on the skin of a user of the wet wipe. The activation meansare included in a core composition that, as described herein, mayoptionally include one or more encapsulating layers, moisture protectivelayers, and fugitive layers to impart various characteristics upon theactivation means and the products in which they are used. Surprisingly,it has been found that when a supersaturated solution and an activationmeans are separately incorporated into a wet wipe, and then allowed tocome into contact upon wipe use, the wet wipe is warmed to allow for acomforting feel to the skin. In one embodiment, one or more surfactantsmay also be included with either the composition including thesupersaturated solution or the core composition including the activationmeans, or both in the products. The addition of the surfactant willdesirably increase the speed of the dissolution of the core composition(and its components) into the composition including the supersaturatedsolution. Additional ingredients such as biocide agents may also beincluded on the surface of the personal care product to produce animproved cleansing product such as a biocidal wet wipe.

Although discussed primarily herein in relation to warming by contactingthe supersaturated solution with an activation means, it will berecognized by one skilled in the art based on the disclosure herein thatother active agents or active ingredients, in addition to, thesupersaturated solution and activation means, may be incorporated intothe wet wipes described herein. For example, the wet wipes may include abiocide agent with the supersaturated solution and activation means.

As noted above, the wet wipes contain a composition comprising asupersaturated solution. Supersaturated solutions can be formed byheating aqueous solutions to a temperature of suitably from about 30° C.(86° F.) to about 100° C. (212° F.), and more suitably, from about 32°C. (90° F.) to about 90° C. (194° F.), and dissolving particles (e.g.,salts or sugars) in the heated aqueous solutions. Typically, the aqueoussolutions are made up of water. Under these heated conditions, moreparticles are capable of dissolving in the solutions, thereby producingsupersaturated solutions. These supersaturated solutions are unstableand will completely crystallize if exposed to an activation means suchas a nucleation site (e.g., a seed crystal) as described more fullybelow. As the solute from the supersaturated solution crystallizes, heatis produced through crystallization enthalpy or latent heat of fusion.

Suitable supersaturated solutions, therefore, are capable of producing ahigh crystallization enthalpy and a high crystallization rate.Generally, the supersaturated solutions are capable of generating acrystallization enthalpy of at least about 70 Joules/gram, and moresuitably at least about 125 Joules/gram. In one embodiment, thesupersaturated solutions are capable of generating a crystallizationenthalpy of from about 70 Joules/gram to about 500 Joules/gram.Additionally, the supersaturated solutions suitably produce acrystallized solid product having a crystallization rate, that is therate at which the solution crystallizes, of at least about 0.01centimeters/second, more suitably at least about 0.03centimeters/second, even more suitably, at least about 0.05centimeters/second, and even more suitably at least about 0.10centimeters/second.

Additionally, the supersaturated solution for use in the wet wipes ofthe present disclosure suitably has a crystallization temperature offrom about 25° C. (77° F.) to about 90° C. (194° F.). More suitably, thesupersaturated solution has a crystallization temperature of from about30° C. (86° F.) to about 60° C. (140° F.). Supersaturated solutions withthese crystallization temperatures are capable of warming the wipe to alevel of giving the perception of warmth without overheating the wipe torisk skin burns.

One particularly suitable example is a supersaturated solution of sodiumacetate. Specifically, to produce a supersaturated solution of sodiumacetate, a solution of sodium acetate and water is heated to atemperature of greater than about 58° C. (136.4° F.) and allowed toslowly cool to room temperature. The resulting supersaturated solutionof sodium acetate will crystallize once it comes into contact with anactivation means such as a sodium acetate seed crystal. Thesupersaturated sodium acetate solution is capable of generating acrystallization enthalpy of 264 Joules/gram, and thus, will produce atemperature to heat the wet wipe of from about 50° C. (122° F.) to about60° C. (140° F.). The generation of this amount of heat will generallylead to an increase in wet wipe temperature of approximately 15° C. (27°F.) to 20° C. (36° F.). Additionally, the supersaturated solution willproduce a crystallized product, sodium acetate trihydrate, having acrystallization rate of as high as about 0.68 centimeters/second.

Other suitable supersaturated solutions for use in the wet wipes of thepresent disclosure include, for example, supersaturated solutionsprepared from aqueous solutions of salts or sugars, the salt or sugarbeing selected from the group consisting of sodium sulfate, sodiumthiosulfate, potash alum, calcium nitrate, potassium acetate, ammoniumnitrate, potassium nitrate, lithium acetate, magnesium acetate, chromiumalum, sodium carbonate, magnesium sulfate, sodium borate, sodiumbromide, xylitol, sodium chromate, calcium chloride, magnesium chloride,magnesium nitrate, disodium phosphate, urea nitrate, and hydratesthereof.

Typically, the wet wipe should comprise from about 3.0 grams per squaremeter to about 850 grams per square meter of the composition comprisingthe supersaturated solution. More typically, the wet wipe shouldcomprise from about 30 grams per square meter to about 330 grams persquare meter of the composition, and even more suitably, from about 100grams per square meter to about 210 grams per square meter.

The supersaturated solution typically present in the composition in anamount of from about 70% (by weight composition) to about 99.9% (byweight composition). More suitably, the supersaturated solution ispresent in the composition in an amount of from about 90% (by weightcomposition) to about 99.5% (by weight composition), and even moresuitably, from about 93% (by weight composition) to about 99% (by weightcomposition). As such, the wet wipe should comprise from about 3.0 gramsper square meter to about 600 grams per square meter supersaturatedsolution. More suitably, the wet wipe should include from about 30 gramper square meter to about 300 grams per square meter supersaturatedsolution, and even more suitably, from about 100 grams per square meterto about 200 grams per square meter supersaturated solution.

Additionally, as noted above, when the supersaturated solution is asupersaturated salt solution, the supersaturated salt solution isproduced by dissolving salt in an aqueous solution. Suitably, the saltis present in the aqueous solution in an amount of from about 33% (byweight solution) to about 60% (by weight solution). In one particularlypreferred embodiment, the supersaturated salt solution is asupersaturated sodium acetate salt solution comprising from about 45%(by weight solution) to about 58% (by weight solution) sodium acetate.More suitably, the sodium acetate is present in the supersaturated saltsolution in an amount of from about 50% (by weight solution) to about54% (by weight solution).

When the supersaturated solution is a supersaturated sugar solution, thesupersaturated sugar solution is produced by dissolving sugar in anaqueous solution. Suitably, the sugar is present in the aqueous solutionin an amount of from about 33% (by weight solution) to about 60% (byweight solution).

In one embodiment, the composition comprising the supersaturatedsolution further includes a gelling agent, wherein upon contact betweenthe supersaturated solution and the gelling agent, a gelled compositionis formed. By forming a gelled composition, the supersaturated solutioncan be evenly distributed within the personal care product without usingan additional support layer such as a fibrous sheet as described in theembodiment below. Suitably, the supersaturated solution is present inthe gelled composition in an amount of from about 70% (by weight gelledcomposition) to about 99.9% (by weight gelled composition). Moresuitably, the supersaturated solution is present in the gelledcomposition in an amount of from about 90% (by weight gelledcomposition) to about 99.5% (by weight gelled composition), and evenmore suitably from about 93% (by weight gelled composition) to about 99%(by weight gelled composition).

In the embodiment using a gelled composition, the gelled composition ispresent in the wet wipe in an amount of from about 3.0 grams/squaremeter to about 850 grams/square meter. More suitably, the gelledcomposition is present in the wet wipe in an amount of from about 30gram/square meter to about 330 grams/square meter, and even moresuitably, from about 100 grams/square meter to about 210 grams/squaremeter.

As noted above, in addition to the supersaturated solution, the gelledcomposition includes a gelling agent. Any gelling agent known in the artsuitable for gelling the composition may be used in the presentdisclosure. For example, suitable gelling agents include fumed silicaand laponite clay. Additional gelling agents are described in U.S. Pat.Nos. 5,058,563, issued to Charles Manker (Oct. 22, 1991) and 5,339,796,issued to Charles Manker (Aug. 23, 1994), which are both herebyincorporated by reference in their entireties to the extent they areconsistent herewith.

Additionally, viscosity increasing agents are suitable for use asgelling agents. Suitable viscosity increasing agents include aqueousviscosity increasing agents, for example, acetamide MEA, acrylamidecopolymers, acrylamide/sodium acrylate copolymer, acrylamide/sodiumacryloyldimethyltaurate copolymer, acrylates/acetoacetoxyethylmethacrylate copolymer, acrylates/beheneth-25 methacrylate copolymer,acrylates/C10-C30 alkyl acrylate crosspolymer, actylates/ceteth-20itaconate copolymer, acrylates/ceteth-20 methacrylate copolymer,actylates/laureth-25 methacrylate, acrylates/pameth-25 acrylatecopolymer, acrylates/palmeth-25 itaconate copolymer,acrylates/steareth-50 acrylate copolymer, acrylates/steareth-20itaconate copolymer, acrylates/steareth-20 methacrylate copolymer,acrylates/stearyl methacrylate copolymer, acrylates/vinyl isodecanoatecrosspolymer, acrylic acid/acrylonitrogens copolymer, adipic acid/methylDEA crosspolymer, agar, agarose, alcaligenes polysaccharides, algin,alginic acid, almondamide DEA, almondamidopropyl betaine,aluminum/magnesium hydroxide stearate, ammoniumacrylates/acrylonitrogens copolymer, ammonium acrylates copolymer,ammonium acryloyldimethyltaurate/vinyl formamide copolymer, ammoniumacryloyldimethyltaurate/VP copolymer, ammonium alginate, ammoniumchloride, ammonium polyacryloyldimethyl taurate, ammonium sulfate,amylopectin, apricotamide DEA, apricotamidopropyl betaine, arachidylalcohol, arachidyl glycol, Arachis hypogaea (Peanut) flour, ascorbylmethylsilanol pectinate, astragalus gummifer gum, attapulgite, Avenasativa (Oat) kernel flour, avocadamide DEA, avocadamidopropyl betaine,azelamide MEA, babassuamide DEA, babassuamide MEA, babassuamidopropylbetaines, behenamide DEA, behenamide MEA, behenamidopropyl betaine,behenyl betaine, bentonite, butoxy chitosan, caesalpinla spinosa gum,calcium alginate, calcium carboxymethyl cellulose, calcium carrageenan,calcium chloride, calcium potassium carbomer, calcium starchoctenylsuccinate, C20-C40 alkyl stearate, canolamidopropyl betaine,capramide DEA, capryl/capramidopropyl betaine, carbomer, carboxybutylchitosan, carboxymethyl cellulose acetate butyrate, carboxymethylchitin, carboxymethyl chitosan, carboxymethyl dextran, carboxymethylhydroxyethylcellulose, carboxymethyl hydroxypropyl guar, camitine,cellulose acetate propionate carboxylate, camitine, cellulose acetatepropionate carboxylate, cellulose gum, ceratonia siliqua gum, cetearylalcohol, cetyl alcohol, cetyl babassuate, cetyl betaine, cetyl glycol,cetyl hydroxyethylcellulose, chimyl alcohol, cholesterol/HDI/pullulancopolymer, cholesteryl hexyl dicarbamate pullulan, citrus Aurantiumdulois (Orange) peel extract, cocamide DEA, cocamide MEA, cocamide MIPA,cocamidoethyl betaine, cocamidopropyl betaine, cocamidopropylhydroxysultaine, coco-betaine, coco-hydroxysultaine, coconut alcohol,coco/oleamidopropyl betaine, coco-sultaine, cocoyl sarcosinamide DEA,cornamide/cocamide DEA, cornamide DEA, croscarmellose, cyamopsistetragonoloba (guar) gum, decyl alcohol, decyl betaine, dehydroxanthangum, dextrin, dibenzylidene sorbitol, diethanolaminooleamide DEA,diglycol/CHDM/isophthalates/SIP copolymer, dihydroabietyl behenate,dihydrogenated tallow benzylmonium hectorite, dihydroxyaluminumaminoacetate, dimethicone/PEG-15 crosspolymer, dimethicone propylPG-betaine, DMAPA acrylates/acrylic acid/acrylonitrogens copolymer,erucamidopropyl hydroxysultaine, ethylene/sodium acrylate copolymer,gelatin, gellan gum, glyceryl alginate, glycine soja (Soybean) flour,guar hydroxypropyltrimonium chloride, hectorite, hyluronic acid,hydrated silica, hydrogenated potato starch, hydrogenated tallow,hydrogenated tallowamide DEA, hydrogenated tallow betaine, hydroxybutylmethylcellulose, hydroxyethyl acrylate/sodium acryloyldimethyl tauratecopolymer, hydroxyethylcellulose, hydroxyethyl chitosan, hydroxyethylethylcellulose, hydroxyethyl stearamide-MIPA,hydroxylauryl/hydroxymyristyl betaine, hydroxypropylcellulose,hyroxypropyl chitosan, hydroxylpropyl ethylenediamine carbomer,hydroxypropyl guar, hydroxylpropyl methylcellulose, hydroxylpropylmethylcellulose stearoxy ether, hydroxypropyl starch, hydroxypropylstarch phosphate, hydroxypropyl xanthan gum, hydroxystearamide DEA,isobutylene/sodium maleate copolymer, isostearamide DEA, isostearamideMEA, isostearmaide MIPA, isosteamidopropyl betaine, lactamide MEA,lanolinamide DEA, lauramide DEA, lauramide MEA, lauramide MIPA,lauramide/myristamide DEA, lauramidopropyl betaine, lauramidopropylhydroxysultaine, lauramino bispropanediol, lauryl alcohol, laurylbetaine, lauryl hydroxysultaine, lauryl sultaine, lecithinamide DEA,linoleamide DEA, linoleamide MEA, linoleaide MIPA, lithium magnesiumsilicate, lithium magnesium sodium silicate, Macrocystis pyrifera(Kelp), magnesium alginate, magnesium/aluminum/hydroxide/carbonate,magnesium aluminum silicate, magnesium silicate, magnesium trisilicate,methoxy PEG-22/dodecyl glycol copolymer, methylcellulose, methylethylcellulose, methyl hydroxyethylcellulose, microcrystallinecellulose, milkamidopropyl betaine, minkamide DEA, minkamidopropylbetaine, MIPA-myristate, montmorillonite, moroccan lava clay,myristamide DEA, myristamide MEA, myristamide MIPA, myristamidopropylbetaine, myristamidopropyl hydroxysultaine, myristyl alcohol, myristylbetaine, natto gum, nonoxynyl hydroxylethylcellulose, oatamide MEA,oatamidopropyl betaine, octacosanyl glycol isostearate, octadecene/macopolymer, oleamide DEA, oleamide MEA, oleamide MIPA, oleamidopropylbetaine, oleamidopropyl hydroxysultaine, oleyl betaine, olivamide DEA,olivamidopropyl hydroxysultaine, oliveamide MEA, palmamide DEA,palmamide MEA, palmamide MIPA, palmamidopropyl betaine, palm kernelalcohol, palm kernelamide DEA, palm kernelamide MEA, palm kernelamideMIPA, palm kernelamidopropyl betaine, peanutamide MEA, peanutamide MIPA,pectin, PEG-800, PEG-crosspolymer, PEG-150/decyl alcohol/SMDI copolymer,PEG-175 dilsostearate, PEG-190 distearate, PEG-15 glyceryl tristearate,PEG-140 glyceryl tristearate, PEG-240/HDI copolymerbis-decyltetradeceth-20 ether, PEG-100/IPDI copolymer,PEG-180/laureth-50/TMMG copolymer, PEG-10/lauryl dimethiconecrosspolymer, PEG-15/lauryl dimethicone crosspolymer, PEG-2M, PEG-5M,PEG-7M, PEG-9M, PEG-14M, PEG-20M, PEG-23M, PEG-25, PEG-45M, PEG-65M,PEG-90M, PEG-115M, PEG-160M, PEG-120 methyl glucose trioleate,PEG-180/octoxynol-4/TMMG copolymer, PEG-150 pentaerythrityltetrastearate, PEG-4 rapeseedamide, PEG-150/stearyl alcohol/SMDIcopolymer, Phaseolus anguilaris seed powder, Polianthes tuberosaextract, polyacrylate-3, polyacrylic acid, polycyclopentadiene,polyether-1, polyethylene/isopropyl maleate/MA copolyol, polyglyceryl-3disiloxane dimethicone, polyglyceryl-3 polydimethylsiloxyethyldimethicone, polymethacrylic acid, pokyquaternium-52, polyvinyl alcohol,potassium alginate, potassium aluminum polyacrylate, potassium carbomer,potassium carrageenan, potassium chloride, potassium palmate, potassiumpolyacrylate, potassium sulfate, potato starch modified, PPG-2 cocamide,PPG-1 hydroxyethyl caprylamide, PPG-2 hydroxyethyl cocamide, PPG-2hydroxyethyl coco/isostearamide, PPG-3 hydroxyethyl soyamide, PPG-14laureth-60 hexyl dicarbamate, PPG-14 laureth-60 isophoryl dicarbamate,PPG-14 palmeth-60 hexyl dicarbamate, propylene glycol alginate,PVP/decene copolymer, PVP montmorillonite, Pyrus cydonia seed, Pyrusmalus (Apple) fiber, rhizobian gum, ricebranamide DEA, ricinoleamideDEA, ricinoleamide MEA, ricinoleamide MIPA, ricinoleamidopropyl betaine,ricinoleic acid/adipic acid/AEEA copolymer, rosa multiflora flower was,sclerotium gum, sesamide DEA, sesamidopropyl betaine, sodiumacrylate/acryloyldimethyl taurate copolymer, sodium acrylates/acroleincopolymer, sodium acrylates/acrylonitrogens copolymer, sodium acrylatescopolymer, sodium acrylates crosspolymer, sodium acrylates/vinylisodecanoate crosspolymer, sodium acrylate/vinyl alcohol copolymer,sodium carbomer, sodium carboxymethyl chitin, sodium carboxymethyldextran, sodium carboxymethyl beat-glucan, sodium carboxymethyl starch,sodium carrageenan, sodium cellulose sulfate, sodium chloride, sodiumcyclodextrin sulfate, sodium hydroxypropyl starch phosphate, sodiumisooctylene/MA copolymer, sodium magnesium fluorosilicate, sodiumoleate, sodium palmitate, sodium palm kernelate, sodium polyacrylate,sodium polyacrylate starch, sodium polyacryloyldimethyl taurate, sodiumpolygamma-glutamate, sodium polymethyacrylate, sodium polystyrenesulfonate, sodium silicoaluminate, sodium starch octenylsuccinate,sodium stearate, sodium stearoxy PG-hydroxyethylcellulose sulfonate,sodium styrene/acrylates copolymer, sodium sulfate, sodium tallowate,sodium tauride acrylates/acrylic acid/acrylonitrogens copolymer, sodiumtocopheryl phosphate, Solanum tuberosum (potato) starch soyamide DEA,soyamidopropyl betaine, starch/acrylates/acrylamide copolymer, starchhydroxypropyltrimonium chloride, stearamide AMP stearamide DEA,stearamide DEA-distearate, stearamide DIBA-stearate, stearamide MEA,stearamide MEA-stearate, stearamide MIPA, stearamidopropyl betaine,steareth-60 cetyl ether, steareth-100/PEG-136/HDI copolymer, stearylalcohol, stearyl betaine, Sterculia urens gum, syntheticfluorphlogopite, tallamide DEA, tallow alcohol, tallowamide DEA,tallowamide MEA, tallowamidopropyl betaine, tallowamidopropylhydroxysultaine, tallowamine oxide, tallow betaine, tallowdihydroxylethyl betaine, Tamarindus indica seed gum, tapioca starch,TEA-alginate, TEA-carbomer, TEA-hydrochlorite, trideceth-2 carboxamideMEA, tridecyl alcohol, triethylene glycol dibenzoate, trimethyl pentanolhydroxyethyl ether, triticum vulgare (Wheat) germ powder, triticumvulgare (Wheat) kernel flour, triticum vulgare (Wheat) starch,tromethamine acrylates/acrylonitrogens copolymer, tromethamine magnesiumaluminum silicate, undecyl alcohol, undecyulenamide DEA, undecylenamideMEA, undecylenamdopropyl betaine, welan gum, wheat germamide DEA, wheatgermamidopropyl betaine, xanthan gum, yeast beta-glucan, yeastpolysaccharides, Zea mays (Corn) starch, and combinations thereof.

The gelling agents are suitably present in the gelled composition in anamount of from about 0.1% (by weight gelled composition) to about 30%(by weight gelled composition). More suitably, the gelling agents arepresent in the gelled composition in an amount of from about 0.5% (byweight gelled composition) to about 10% (by weight gelled composition),and even more suitably, from about 1% (by weight gelled composition) toabout 7% (by weight gelled composition).

In addition to the supersaturated solution and the gelling agent (ifpresent), the composition can optionally comprise a plasticizer. As thesupersaturated solution crystallizes, the wipe can become stiff andinflexible. As such, a plasticizer can be added to increase flexibility.Suitable plasticizers can include, for example, mineral oil, glycerine,soaps, fatty acids, sands, and combinations thereof. The plasticizer canbe present in the composition in an amount of from about 0.1% (by weightcomposition) to about 30% (by weight composition). More suitably, theplasticizer can be present in the gelled composition in an amount offrom about 1% (by weight composition) to about 10% (by weightcomposition).

Additionally, the composition can optionally include an emulsifyingagent in combination with a plasticizer to ensure that the plasticizeris sufficiently dispersed within the composition. One particularlysuitable emulsifying agent includes polysorbate 20. Additional suitableemulsifying agents are described in the International CosmeticIngredient Dictionary and Handbook, 10th Edition (2004), vol. 3 on pages2276-2285, which is hereby incorporated by reference to the extent it isconsistent. When an emulsifying agent is included in the composition,the emulsifying agent is present in the composition in an amount of fromabout 0.1% (by weight composition) to about 15% (by weight composition).More suitably, the emulsifying agent is present in the composition in anamount of from about 1% (by weight composition) to about 10% (by weightcomposition).

In addition to the compositions including a supersaturated solution (andany other optional ingredients), the wet wipes of the present disclosureinclude a core composition comprising one or more activation means toinitiate crystallization of the supersaturated solution.

Typically, the activation means is comprised of one or more seedcrystals having a similar chemistry as compared to the supersaturatedsolution. More particularly, a suitable activation means will havecrystallographic data being within about 15% of that of the material tobe crystallized in the supersaturated solution. As such, in theembodiment wherein the supersaturated solution is a supersaturated saltsolution, the activation means is suitably a salt selected from thegroup consisting of sodium acetate, sodium sulfate, sodium sulfatedecahydrate, sodium thiosulfate, potash alum, calcium nitrate, potassiumacetate, ammonium nitrate, potassium nitrate, lithium acetate, magnesiumacetate, chromium alum, sodium carbonate, magnesium sulfate, sodiumborate, sodium bromide, sodium chromate, calcium chloride, magnesiumchloride, magnesium nitrate, disodium phosphate, urea nitrate, andhydrates thereof. In the alternative embodiment, the supersaturatedsolution is a supersaturated sugar solution, wherein the activationmeans is suitably a sugar such as xylitol.

The activation means is suitably present in the core composition in anamount of from about 0.1% (by weight) to about 80% (by weight). Moresuitably, the activation means is present in the core composition in anamount of from about 0.1% (by weight) to about 50% (by weight), and evenmore suitably, from about 0.1% (by weight) to about 10% (by weight).

The activation means utilized in the core composition generally has aparticle size of from about 0.01 micrometers to about 500 micrometers,desirably from about 1 micrometers to about 100 micrometers, desirablyfrom about 5 micrometers to about 50 micrometers, and more desirablyfrom about 10 micrometers to about 30 micrometers to facilitatesubstantial and continuous crystallization of the supersaturatedsolution. Although many activation means as described herein arecommercially available in a number of particle sizes, it will berecognized by one skilled in the art that any number of techniques canbe used to grind and produce the desired particle sizes.

Along with the activation means, a surfactant may optionally be includedin the core composition. As used herein, “surfactant” is intended toinclude surfactants, dispersants, gelling agents, polymeric stabilizers,structurants, structured liquids, liquid crystals, Theologicalmodifiers, grinding aids, defoamers, block copolymers, and combinationsthereof. If a surfactant is utilized, it should be substantiallynon-reactive with the activation means. A surfactant may be added alongwith a activation means and a matrix material as described below to thecore composition as a grinding and mixing aid for the activation meansand to reduce the surface tension of the core composition and allow forbetter mixing with the supersaturated solution.

Any one of a number of surfactant types including anionic, cationic,nonionic, zwitterionic, and combinations thereof can be utilized in thecore composition. One skilled in the art will recognize, based on thedisclosure herein, that different activation means may benefit from onetype of surfactant more than another; that is, the preferred surfactantfor one chemistry may be different than the preferred surfactant foranother. Particularly desirable surfactants will allow the corecomposition including the activation means and surfactant mixture tohave a suitable viscosity for thorough mixing; that is, the surfactantwill not result in the mixture having an undesirably high viscosity.Examples of commercially available surfactants suitable for use in thecore composition include, for example, Antiterra 207 (BYK Chemie,Wallingford, Conn.) and BYK-P104 (BYK Chemie).

When included in the core composition, the surfactant is generallypresent in an amount of from about 0.01% (by weight core composition) toabout 50% (by weight core composition), desirably from about 0.1% (byweight core composition) to about 25% (by weight core composition), moredesirably from about 0.1% (by weight core composition) to about 10% (byweight core composition), more desirably from about 1% (by weight corecomposition) to about 5% (by weight core composition), and still moredesirably about 1% (by weight core composition).

The core composition may optionally include a matrix material inaddition to the activation means alone or in combination with theactivation means and surfactant. The matrix material included in thecore composition is used as a carrying or bulking agent for othercomponents of the core composition, including, for example, theactivation means. Specifically, the matrix material can provide forprotection to the activation means throughout processing andtransportation of the wet wipes. Although generally preferred to be aliquid material, the matrix material may also be a low melting materialthat is a solid at room temperature. The matrix material is desirably amaterial that is emulsifiable in water. Preferred liquid matrixmaterials include oils commonly used in commercial cosmetic applicationsthat may impart some skin benefit to the user, such as a moisturizing orlubricating benefit. Generally, these oils are hydrophobic oils.

Specific examples of suitable liquid matrix materials include, forexample, mineral oil, petrolatum, isopropyl myristate, silicones,copolymers such as block copolymers, waxes, butters, exotic oils,dimethicone, thermoionic gels, plant oils, animal oils, and combinationsthereof. One preferred material for use as the matrix material ismineral oil. The matrix material is generally present in the corecomposition in an amount of from about 1% (by weight core composition)to about 99% (by weight core composition), desirably from about 10% (byweight core composition) to about 95% (by weight core composition), moredesirably from about 15% (by weight core composition) to about 75% (byweight core composition), more desirably from about 20% (by weight corecomposition) to about 50% (by weight core composition), more desirablyfrom about 25% (by weight core composition) to about 45% (by weight corecomposition), and even more desirably from about 30% (by weight corecomposition) to about 40% (by weight core composition).

As will be described in more detail below, in one embodiment, during themanufacturing process for the core composition, the contents of the corecomposition such as the activation means (and optionally, the matrixmaterial and the surfactant) are introduced into a liquid solution suchas a sodium alginate bath. During contact with this bath, it may bepossible for the activation means present in the core composition todissolve in the sodium alginate bath. This contact can result in a lossof potency and deactivation of the activation means and render theresulting core composition ineffective for its intended purpose. Assuch, in one embodiment of the present disclosure, the activation meansincluded in the core composition is substantially completely surroundedby a wax material prior to being introduced into the core compositionand ultimately into the sodium alginate bath. This wax material mayprovide the activation means with temporary protection during thetimeframe of exposure to the sodium alginate bath; that is, the waxmaterial may keep sodium alginate from contacting the activation means.Although the wax material provides protection of the activation meansduring creation of the core composition, in one embodiment it willgradually dissolve away and off of the activation means within the corecomposition over time; that is, the wax material dissolves into thematrix material of the core composition over time and off of theactivation means so that the activation means can be directly contactedwith the supersaturated solution upon activation in a wipe or otherproduct.

In an alternative embodiment, the wax material does not substantiallydissolve into the core composition and off of the activation means butis removed from the activation means at the time of use through shearingor disruption of the wax material; that is, the wax material ismechanically broken off of the activation means to allow the activationmeans access to the supersaturated solution.

It is generally desirable to have substantially complete coverage of theactivation means with the wax material to ensure that the activationmeans is not susceptible to contact with the sodium alginate bath duringthe introduction of the core composition into the liquid as describedherein. When contacted with a substantially continuous layer of waxmaterial, the core composition including the activation means can beencapsulated in the liquid environment without the activation meanslosing potency. Generally, the wax material may be applied to theactivation means in from about 1 to about 30 layers, desirably in fromabout 1 to about 10 layers.

Generally, the wax material is present on the activation means in anamount of from about 1% (by weight activation means) to about 50% (byweight activation means), desirably from about 1% (by weight activationmeans) to about 40% (by weight activation means), more desirably fromabout 1% (by weight activation means) to about 30% (by weight activationmeans), and even more desirably from about 1% (by weight activationmeans) to about 20% (by weight activation means). At these levels, thereis sufficient wax material present on the activation means to providethe desired level of protection, yet not too much to keep it fromdissolving over time into the core composition to allow for thesupersaturated solution to access the activation means at the desiredtime.

Suitable wax materials for coating the heating agent are relatively lowtemperature melting wax materials. Although other low temperaturemelting materials can be used to coat the activation means in accordancewith the present disclosure, low temperature melting wax materials aregenerally preferred. In one embodiment, the wax material has a meltingtemperature of less than about 140° C., desirably less than about 90° C.to facilitate the coating of the activation means as described below.

Suitable wax materials for use in coating the activation means includetetracosane, pentacosane, hexacosane, heptacosane, octacosane, glyceryldistearate, canola wax, hydrogenated cottonseed oil, hydrogenatedsoybean oil, castor wax, rapeseed wax, beeswax, carnauba wax, candelillawax, microwax, polyethylene, polypropylene, epoxies, long chainalcohols, long chain esters, long chain fatty acids, hydrogenated plantoils, hydrogenated animal oils, microcrystalline waxes, metal stearatesand metal fatty acids, and combinations thereof.

In one suitable embodiment, the core composition including theactivation means alone or in combination with the matrix material and/orsurfactant as described herein may include a number of layers.Specifically, the core composition includes an encapsulation layercompletely surrounding the core composition, a moisture protective layerthat surrounds the encapsulation layer, and a fugitive layer thatsurrounds the moisture protective layer. Each of these layers, each ofwhich is optional, is more thoroughly discussed below.

When the core composition is surrounded by an encapsulation layer, theencapsulated core composition is desirably of a size such that, whenincorporated into a personal care product such as a wet wipe, theycannot readily be felt on the skin by the user. Generally, theencapsulated core compositions have a diameter of from about 5micrometers to about 10,000 micrometers, desirably from about 5micrometers to about 5000 micrometers, desirably from about 50micrometers to about 1000 micrometers, and still more desirably fromabout 300 micrometers to about 700 micrometers.

The encapsulation layer allows the core composition including theactivation means to undergo further processing and use without a loss ofstructural integrity; that is, the encapsulation layer providesstructural integrity to the core composition and its contents to allowfor further processing.

In one embodiment, the encapsulation layer may be comprised of apolymeric material, a crosslinked polymeric material, a metal, a ceramicor a combination thereof, that results in a shell material that may beformed during manufacturing. Specifically, the encapsulation layer maybe comprised of crosslinked sodium alginate, anionic dispersed latexemulsions, crosslinked polyacrylic acid, crosslinked polyvinyl alcohol,crosslinked polyvinyl acetate, silicates, carbonates, sulfates,phosphates, borates, polyvinyl pyrolidone, PLA/PGA, urea formaldehyde,melamine formaldehyde, polymelamine, crosslinked starch, nylon, ureas,hydrocolloids, clays, and combinations thereof. One particularlypreferred crosslinked polymeric system is crosslinked sodium alginate.

The encapsulation layer present around the core composition generallyhas a thickness of from about 0.1 micrometers to about 500 micrometers,desirably from about 1 micrometer to about 100 micrometers, moredesirably from about 1 micrometer to about 50 micrometers, moredesirably from about 1 micrometer to about 20 micrometers, and even moredesirably from about 10 micrometers to about 20 micrometers. At thesethicknesses, the crosslinked polymeric layer has a sufficient thicknessto provide its intended function. The encapsulation layer may be onediscrete layer, or may be comprised of multiple layers added in one ormore steps. Suitable methods for measuring the thickness of theencapsulation layer (once fractured), and the other optional layersdescribed herein, include Scanning Electron Microscopy (SEM) and OpticalMicroscopy.

Generally, the encapsulation layer will be present in from about 1 layerto about 30 layers, desirably in from about 1 layer to about 20 layers,and more desirably in from about 1 layer to about 10 layers to providefurther protection.

The core composition as described herein may optionally comprise amoisture protective layer surrounding the encapsulation layer to producea substantially fluid-impervious encapsulated core composition. As usedherein, “fluid” is meant to include both water (such as thesupersaturated solution and other fluids) and oxygen (and other gases)such that “fluid-impervious” includes both water-impervious andoxygen-impervious. Although referred to throughout herein as a “moistureprotective layer,” one skilled in the art based on the disclosure hereinwill recognize that this layer may be both “moisture protective” and“oxygen protective;” that is, the layer will protect and insulate thecore composition and its contents from both water and oxygen.

When present, the moisture protective layer substantially completelysurrounds the encapsulation layer described above. The moistureprotective layer will help to ensure that the core composition and itscontent (i.e., activation means) will not come into contact with thesupersaturated solution and allow premature crystallization.

The moisture protective layer may be present over the encapsulationlayer in one layer or in multiple layers. Desirably, the moistureprotective layer will be present in from about 1 layer to about 30layers, desirably in from about 1 layer to about 20 layers, and moredesirably in from about 1 layer to about 10 layers to provide furtherprotection. As noted above, the moisture protective layer substantiallycompletely surrounds the encapsulation layer to keep the supersaturatedsolution from reaching the internal contents of the core composition andultimately the activation means. To ensure the moisture protective layersubstantially completely covers the encapsulation layer, multiple layersmay be utilized as noted above. Each of the moisture protective layersgenerally has a thickness of from about 1 micrometer to about 200micrometers, desirably from about 1 micrometer to about 100 micrometers,and even more desirably from about 1 micrometer to about 50 micrometers.

The moisture protective layer may comprise any number of materialsincluding, for example, polyols in combination with isocynate,styrene-acrylate, vinyl toluene-acrylate, styrene-butadiene,vinyl-acrylate, polyvinyl butyral, polyvinyl acetate, polyethyleneterephthalate, polypropylene, polystyrene, polymethyl methacrylate, polylactic acid, polyvinylidene chloride, polyvinyldichloride, polyethylene,alkyl polyester, carnauba wax, hydrogenated plant oils, hydrogenatedanimal oils, fumed silica, silicon waxes, fluorinated chlorosilanes,ethoxy fluorochemicals, methoxyfluorochemicals, titanium dioxide,silicon dioxide, metals, metal carbonates, metal sulfates, ceramics,metal phosphates, microcrystalline waxes, and combinations thereof.

In addition to the moisture protective layer, the core composition mayalso optionally be surrounded by a fugitive layer that surrounds themoisture protective layer, if present, or the encapsulating layer if themoisture protective layer is not present. The fugitive layer can act tostabilize and protect the activation means from being exposedprematurely to the supersaturated solution due to mechanical load, orcan provide other benefits. When present over the moisture protectivelayer (or encapsulation layer), the fugitive layer can impart strengthand withstand a given mechanical load until a time when the fugitivelayer is ruptured by the end user or is decomposed or degraded in apredictable manner in the supersaturated solution, usually duringshipment and/or storage of the product prior to use. Consequently, thefugitive layer allows the activation means to survive relatively highmechanical load conditions commonly experienced in shipping and/ormanufacturing.

In one embodiment, the fugitive layer substantially completely surroundsthe moisture protective layer (or the encapsulating layer) such thatthere are substantially no access points to the underlying layer.Alternatively, the fugitive layer may be a non-continuous, porous ornon-porous layer surrounding the moisture protective layer (or theencapsulating layer).

The fugitive layer, similar to the moisture protective layer, may bepresent in multiple layers. Specifically, the fugitive layer may bepresent in anywhere from about 1 to about 30 layers, desirably fromabout 1 to about 20 layers, and more desirably from about 1 to about 10layers. Generally, each fugitive layer may have a thickness of fromabout 1 micrometer to about 200 micrometers, desirably from about 1micrometer to about 100 micrometers, and more desirably from about 1micrometer to about 50 micrometers.

The fugitive layer may be comprised of any one of a number of suitablematerials including, for example, polymers of dextrose and other sugars,starches, alginate, acrylates, polyvinyl alcohol, ethylene oxidepolymers, polyethyleneimine, gums, gum arabic, polyacrylamide,hydroxypropyl cellulose, hydroxypropyl methylcellulose, polyvinylpyrrolidone, poly(2-acrylamido-2-methyl-1-propanesulfonic acid),poly(acrylamido-N-propyltrimethylammonium chloride), and combinationsthereof. One particularly preferred material for use as the fugitivelayer is starch.

In another embodiment, the encapsulated core composition can further besurrounded by petroleum such as petroleum jelly prior to beingincorporated into the product to gel the core composition in aparticular region of the product. It should be recognized that othergelatinous hydrophobic materials such as soft waxes with low meltingpoints may also be used in combination with or in place of the petroleumjelly. Specifically, the petroleum jelly layer can prevent the corecomposition from moving in the product and prematurely contacting thesupersaturated solution. Suitably, the core composition is surroundedfrom about 300% (by weight core composition) to about 100,000% (byweight core composition) petroleum jelly. One particularly preferredpetroleum jelly for surrounding the core composition is Vaseline®Petroleum Jelly.

In another embodiment, the petroleum jelly surrounds the activationmeans prior to the activation means being incorporated into the corecomposition. Suitably, the activation means is surrounded by thepetroleum jelly in an amount of from about 1000% (by weight activationmeans) to about 1,000,000% (by weight activation means) petroleum jelly.

The encapsulated core composition as described herein may bemanufactured in any number of ways as discussed below. The first step inthe manufacturing process is generally to coat the desired activationmeans (e.g., sodium acetate) with a wax material as described aboveprior to incorporating the wax material-coated activation means into thecore composition. As would be recognized by one skilled in the art basedon the disclosure herein, this wax material coating of the activationmeans step is optional and can be eliminated if such a coating is notdesired and the activation means is to be incorporated into the corecomposition without any protective coating.

In one embodiment, the wax material is coated onto the activation meansby blending the activation means and wax material together at anelevated temperature sufficient to melt the wax material in the presenceof the activation means and the melted wax material and activation meansstirred sufficiently to coat the activation means. After the coating ofthe activation means is complete, the mixture is allowed to cool to roomtemperature to allow the wax to solidify on the activation means. Afterthe coated activation means have cooled, they can be ground to thedesired size prior to incorporation into the core composition.

After the grinding of the wax material-coated activation means, it maybe desirable to subject the ground material to a further process toensure that the wax material coating is substantially complete aroundthe activation means. Suitable additional processes include, forexample, spheroidization (high heat fluidization slightly below the melttemperature of the wax material) and ball milling. These additionalprocesses can be used to ensure substantially complete coverage of theactivation means with the wax material.

The wax material-coated (or uncoated) activation means can be used alonein the core composition or can be mixed with the other optionalingredients in the core composition, including the matrix material,surfactant, and encapsulating activator (as described more fully below).As will be further recognized by one skilled in the art, some methods offorming an outer layer on the core composition (i.e., coacervation) maynot require a chemical encapsulating activator to be present in the corecomposition, but may utilize a change in pH, a change in temperature,and/or a change in ionic strength of the liquid solution to initiate theformation of the encapsulating layer around the core composition.Additionally, it will be further recognized by one skilled in the artbased on the disclosure herein that the encapsulating activator, whenpresent, may be located outside of the core composition; that is, theencapsulating activator may be located in the liquid solution forexample, although it is generally desirable to have it located withinthe core composition.

The encapsulating activator, when present in the core composition, canact as a crosslinking agent to crosslink the encapsulating layerdiscussed herein. Once the core composition is introduced into a liquidsolution containing a crosslinkable compound as described below, theencapsulating activator interacts with the crosslinkable compound andcauses it to crosslink on the outer surface of the composition to form acrosslinked shell. Because the encapsulating activator chemically reactswith the crosslinkable compound contained in the liquid solution, theresulting encapsulated core composition may not contain anyencapsulating activator in its final form.

The encapsulating activator may be any activator capable of initiating acrosslinking reaction in the presence of a crosslinkable compound.Suitable encapsulating activators include, for example, polyvalent ionsof calcium, polyvalent ions of copper, polyvalent ions of barium,silanes, aluminum, titanates, chelators, acids, and combinationsthereof. Specifically, the encapsulating activator may be calciumchloride, calcium sulfate, calcium oleate, calcium palmitate, calciumstearate, calcium hypophosphite, calcium gluconate, calcium formate,calcium citrate, calcium phenylsulfonate, and combinations thereof. Apreferred encapsulating activator is calcium chloride.

The encapsulating activator is generally present in the core compositionin an amount of from about 0% (by weight core composition) to about 25%(by weight core composition), desirably from about 0.1% (by weight corecomposition) to about 15% (by weight core composition), and still moredesirably from about 0.1% (by weight core composition) to about 10% (byweight composition).

To produce the core composition including the activation means (whichmay or may not be surrounded by a wax material), matrix material,encapsulating activator and surfactant (if any), the desired amounts ofthese components may be optionally passed through a milling device thatserves to thoroughly mix the components together for further processing.Suitable wet milling operations include, for example, bead milling andwet ball milling. Additionally, processes known to those skilled in theart such as hammer milling and jet milling may be used to first preparethe activation means, and then disperse the treated activation meansinto the core composition containing the matrix material, surfactant andencapsulating activator followed by thorough mixing.

Once the core composition is prepared, it is introduced into a liquidsolution, generally held at room temperature, to activate a crosslinkingreaction to form an outer encapsulating shell that protects the corecomposition and its components (core material) and allows for immediateuse or further processing. Although described herein primarily inreference to a “crosslinking reaction,” it will be recognized by oneskilled in the art based on the disclosure herein that the encapsulationlayer can be formed around the core composition not only by acrosslinking reaction, but also by coacervation, coagulation,flocculation, adsorption, complex coacervation and self-assembly, all ofwhich are within the scope of the present disclosure. As such, the term“crosslinking reaction” is meant to include these other methods offorming the encapsulation layer around the core composition.

One particular advantage of one embodiment described herein is that thepresence of the encapsulating activator in the core composition allowsfor almost instantaneous crosslinking when the core composition isintroduced into the solution containing the crosslinkable compound; thisreduces the potential for unwanted heating agent deactivation. In oneembodiment, the core composition is added dropwise into the liquidcontaining the crosslinkable compound and the beads that form when thedrops contact the liquid are kept separated during the crosslinkingreaction using a sufficient amount of stirring and mixing. It ispreferred to use sufficient stirring and mixing to keep the beadsseparate during the crosslinking reaction to ensure that they remainseparate, individual beads and do not form larger agglomerated massesthat are susceptible to numerous defects. Generally, the drops added tothe liquid solution can have a diameter of from about 0.05 millimetersto about 10 millimeters, desirably from about 0.1 millimeter to about 3millimeters, and still more desirably from about 0.5 millimeters toabout 1 millimeter. Alternatively, the core composition may beintroduced or poured into the liquid solution including thecrosslinkable compound and then subjected to shear sufficient to breakthe paste into small beads for crosslinking thereon.

In one embodiment, the liquid solution includes a crosslinkable compoundthat can be crosslinked in the presence of the encapsulating activatorto form the outer encapsulate shell. Optionally, a surfactant asdescribed herein can also be introduced into the liquid solution tofacilitate crosslinking. When the core composition including theencapsulating activator is introduced into the liquid containing thecrosslinkable compound, the encapsulating activator migrates to theinterface between the core composition and the liquid solution andinitiates the crosslinking reaction on the surface of the corecomposition to allow the encapsulation layer to grow outward toward theliquid solution. The thickness of the resulting encapsulation layersurrounding the core composition can be controlled by (1) controllingthe amount of encapsulating activator included in the core composition;(2) controlling the amount of time the core composition including theencapsulating activator is exposed to the liquid solution including thecrosslinkable compound; and/or (3) controlling the amount ofcrosslinkable compound in the liquid solution. Generally, anencapsulating layer of sufficient and desired thickness can be formedaround the core composition by allowing the core composition to dwell inthe liquid solution including the crosslinkable compound for from about10 seconds to about 40 minutes, desirably from about 5 minutes to about30 minutes, and still more desirably from about 10 minutes to about 20minutes.

It is generally desirable that the liquid solution containing thecrosslinkable compound has a viscosity suitable for allowing sufficientmixing of the formed beads therein; that is, the viscosity of the liquidsolution should not be so high that stirring and mixing is substantiallyimpaired and the ability to keep the formed beads separated reduced. Tothat end, the liquid solution containing the crosslinkable compoundgenerally contains from about 0.1% (by weight liquid solution) to about50% (by weight liquid solution), desirably from about 0.1% (by weightliquid solution) to about 25% (by weight liquid solution) and moredesirably from about 0.1% (by weight liquid solution) to about 1% (byweight liquid solution) crosslinkable compound.

Any number of crosslinkable compounds can be incorporated into theliquid solution to form the encapsulated layer around the corecomposition upon contact with the encapsulating activator. Some suitablecrosslinkable compounds include, for example, sodium alginate, anionicdispersed latex emulsions, polyacrylic acid, polyvinyl alcohol,polyvinyl acetate, silicates, carbonates, sulfates, phosphates, borates,and combinations thereof. A particularly desirable crosslinkablecompound is sodium alginate.

Once a sufficient amount of time has passed for the encapsulating layerto form on the core composition, the formed beads may be removed fromthe liquid including the crosslinkable compound. The resultingencapsulated core composition may optionally be washed several times toremove any crosslinkable compound thereon and dried and are then readyfor use or for further processing. One suitable washing liquid isdeionized water.

In one embodiment, the encapsulated core composition formed as describedabove is subjected to a process to impart a moisture protective layerthereon that surrounds the encapsulated layer that comprises thecrosslinked compound. This moisture protective layer provides theencapsulated core composition with increased protection from thesupersaturated solution; that is, it makes the encapsulated corecomposition substantially fluid impervious and allows the encapsulatedcore composition to survive long term in the supersaturated solutionenvironment and not degrade until the moisture protective layer isruptured by mechanical action. The moisture protective layer may be asingle layer applied onto the encapsulated core composition, or maycomprise several layers one on top of the other.

The moisture protective layer may be applied to the encapsulated corecomposition utilizing any number of suitable processes including, forexample, atomizing or dripping a moisture protective material onto theencapsulated core composition. Additionally, a Wurster coating processmay be utilized. When a solution is used to provide the moistureprotective coating, the solids content of the solution is generally fromabout 0.1% (by weight solution) to about 70% (by weight solution),desirably from about 1% (by weight solution) to about 60% (by weightsolution), and still more desirably from about 5% (by weight solution)to about 40% (by weight solution). Generally, the viscosity of thesolution (at 25° C.) including the moisture protective material is fromabout 0.6 centipoise to about 10,000 centipoise, desirably from about 20centipoise to about 400 centipoise, and still more desirably from about20 centipoise to about 100 centipoise.

In one specific embodiment, a fluidized bed process is utilized toimpart the moisture protective layer on the encapsulated corecomposition. The fluidized bed is a bed or layer of encapsulated corecomposition capsules through which a stream of heated or unheatedcarrier gas is passed at a rate sufficient to set the encapsulatedcapsules in motion and cause them to act like a fluid. As the capsulesare fluidized, a spray of a solution comprising a carrier solvent andthe moisture protective material is injected into the bed and contactsthe capsules imparting the moisture protective material thereon. Thetreated capsules are collected when the desired moisture protectivelayer thickness is achieved. The capsules can be subjected to one ormore fluidized bed processes to impart the desired level of moistureprotective layer.

In another embodiment, the encapsulated core composition, which may ormay not include a moisture protective layer as described above, issubjected to a process for imparting a fugitive layer thereonsurrounding the outermost layer. For example, if the encapsulated corecomposition includes a moisture protective layer, the fugitive layerwould be applied on the capsule such that it substantially completelycovered the moisture protective layer. The fugitive layer can be appliedin a single layer, or may be applied in multiple layers.

The fugitive layer may be applied to the encapsulated core compositionutilizing any number of suitable processes including, for example,atomizing or dripping a fugitive material onto the encapsulated corecomposition. When a solution is used to provide the fugitive coating,the solids content of the solution is generally from about 1% (by weightsolution) to about 70% (by weight solution), desirably from about 10%(by weight solution) to about 60% (by weight solution). The pH of thesolution is generally from about 2.5 to about 11. Generally, theviscosity of the solution (at 25° C.) including the fugitive material isfrom about 0.6 centipoise to about 10,000 centipoise, desirably fromabout 20 centipoise to about 400 centipoise, and still more desirablyfrom about 20 centipoise to about 100 centipoise. Similar to themoisture protective layer, a preferred method of applying the fugitivelayer utilizes a fluidized bed reactor. Also, a Wurster coating processmay also be used.

As noted above, the supersaturated solutions and the activation means asdescribed herein are suitable for use in a number of products, includingwipe products, wraps, such as medical wraps and bandages, headbands,wristbands, helmet pads, personal care products, and the like. Althoughdescribed primarily herein in relation to wipes, it will be recognizedby one skilled in the art that the supersaturated solutions andactivation means described herein could be incorporated into any one ormore of the other products listed above.

Generally, the wipes of the present disclosure including thesupersaturated solutions and activation means can be wet wipes or drywipes. As used herein, the term “wet wipe” means a wipe that includesgreater than about 70% (by weight substrate) moisture content. As usedherein, the term “dry wipe” means a wipe that includes less than about10% (by weight substrate) moisture content. Specifically, suitable wipesfor use in the present disclosure can include wet wipes, hand wipes,face wipes, cosmetic wipes, household wipes, industrial wipes, and thelike. Particularly preferred wipes are wet wipes, and other wipe-typesthat include a solution.

Materials suitable for the substrate of the wipes are well know to thoseskilled in the art, and are typically made from a fibrous sheet materialwhich may be either woven or nonwoven. For example, suitable materialsfor use in the wipes may include nonwoven fibrous sheet materials whichinclude meltblown, coform, air-laid, bonded-carded web materials,hydroentangled materials, and combinations thereof. Such materials canbe comprised of synthetic or natural fibers, or a combination thereof.Typically, the wipes of the present disclosure define a dry basis weightof from about 25 grams per square meter to about 120 grams per squaremeter and desirably from about 40 grams per square meter to about 90grams per square meter.

In one particular embodiment, the wipes of the present disclosurecomprise a coform basesheet material of polymer fibers and absorbentfibers having a basis weight of from about 60 to about 80 grams persquare meter and desirably about 75 grams per square meter. Such coformbasesheets are manufactured generally as described in U.S. Pat. Nos.4,100,324, issued to Anderson, et al. (Jul. 11, 1978); 5,284,703, issuedto Everhart, et al. (Feb. 8, 1994); and 5,350,624, issued to Georger, etal. (Sep. 27, 1994), which are incorporated by reference to the extentto which they are consistent herewith. Typically, such coform basesheetscomprise a gas-formed matrix of thermoplastic polymeric meltblown fibersand cellulosic fibers. Various suitable materials may be used to providethe polymeric meltblown fibers, such as, for example, polypropylenemicrofibers. Alternatively, the polymeric meltblown fibers may beelastomeric polymer fibers, such as those provided by a polymer resin.For instance, Vistamaxx® elastic olefin copolymer resin designatedVM2380, available from ExxonMobil Corporation (Houston, Tex.) or KRATONG-2755, available from Kraton Polymers (Houston, Tex.) may be used toprovide stretchable polymeric meltblown fibers for the coformbasesheets. Other suitable polymeric materials or combinations thereofmay alternatively be utilized as known in the art.

As noted above, the coform basesheet material additionally may comprisevarious absorbent cellulosic fibers, such as, for example, wood pulpfibers. Suitable commercially available cellulosic fibers for use in thecoform basesheets can include, for example, NF 405, which is achemically treated bleached southern softwood Kraft pulp, available fromWeyerhaeuser Co. of Federal Way (Washington); NB 416, which is ableached southern softwood Kraft pulp, available from Weyerhaeuser Co.;CR-0056, which is a fully debonded softwood pulp, available fromBowater, Inc. (Greenville, S.C.); Golden Isles 4822 debonded softwoodpulp, available from Koch Cellulose (Brunswick, Ga.); and SULPHATATE HJ,which is a chemically modified hardwood pulp, available from Rayonier,Inc. (Jesup, Ga.).

The relative percentages of the polymeric meltblown fibers andcellulosic fibers in the coform basesheet material can vary over a widerange depending upon the desired characteristics of the wipes. Forexample, the coform basesheet material may comprise from about 10 weightpercent to about 90 weight percent, desirably from about 20 weightpercent to about 60 weight percent, and more desirably from about 25weight percent to about 35 weight percent of the polymeric meltblownfibers based on the dry weight of the coform basesheet being used toprovide the wipes.

In an alternative embodiment, the wipes of the present disclosure cancomprise a composite which includes multiple layers of materials. Forexample, the wipes may include a multi-layer composite which includesone or more elastomeric films or meltblown layers between two coformlayers as described above. In such a configuration, the coform layersmay define a basis weight of from about 15 grams per square meter toabout 30 grams per square meter and the elastomeric layer(s) may includea film material such as a polyethylene metallocene film. Such compositesare manufactured generally as described in U.S. Pat. No. 6,946,413,issued to Lange, et al. (Sep. 20, 2005), which is hereby incorporated byreference to the extent it is consistent herewith.

In accordance with the present disclosure, the composition including thesupersaturated solution is capable of generating heat to produce awarming sensation in the wipe upon being contacted with the contents(i.e., activation means) of the core composition.

In one embodiment, the wipe is a wet wipe comprising a wetting solutionin addition to the fibrous sheet material, the composition including thesupersaturated solution, and the core composition including theactivation means. The wetting solution can be any wetting solution knownto one skilled in the wet wipe art. Generally, the wetting solution caninclude water, emollients, surfactants, preservatives, chelating agents,pH adjusting agents, skin conditioners, fragrances, and combinationsthereof. For example, one suitable wetting solution for use in the wetwipe of the present disclosure comprises about 98% (by weight) water,about 0.6% (by weight) surfactant, about 0.3% (by weight) humectant,about 0.3% (by weight) emulsifier, about 0.2% (by weight) chelatingagent, about 0.35% (by weight) preservative, about 0.002% (by weight)skin conditioning agent, about 0.03% (by weight) fragrance, and about0.07% (by weight) pH adjusting agent. One specific wetting solutionsuitable for use in the wet wipe of the present disclosure is describedin U.S. Pat. No. 6,673,358, issued to Cole et al. (Jan. 6, 2004), whichis incorporated herein by reference to the extent it is consistentherewith.

It has been determined that the ideal temperature for a wipe to beutilized is a temperature of from about 30° C. to about 40° C. (86°F.-104° F.). A conventional wipe will typically be stored at roomtemperature (about 23° C. (73.4° F.). As such, when the core compositionruptures, and releases the activation means, and the activation meanscontacts the supersaturated solution, a warming sensation is produced,increasing the temperature of the solution and wipe by at least about 5°C. More suitably, the temperature of the solution and wipe is increasedby at least about 10° C., even more suitably, increased by at leastabout 15° C., and even more suitably increased by at least about 20° C.or more.

Generally, the elapsed time between the dispensing of a wipe product anduse of the product is about 2 seconds or less, and typically is about 6seconds or less. As such, once the core composition of the presentdisclosure is ruptured and the activation means is contacted with thesupersaturated solution, the crystallization reaction begins to generateheat and a warming sensation is suitably perceived in less than about 20seconds. More suitably, the warming sensation is perceived in less thanabout 10 seconds, even more suitably, in less than about 5 seconds, andeven more suitably, in less than about 2 seconds.

Additionally, once the warming sensation begins, the warming sensationof the wipe product is suitably maintained for at least about 5 seconds.More suitably, the warming sensation is maintained for at least about 8seconds, even more suitably for at least about 15 seconds, even moresuitably for at least about 20 seconds, even more suitably for at leastabout 40 seconds, and even more suitably for at least about 1 minute.

To generate the temperature increase described above, the wipes of thepresent disclosure suitably comprise at least about 3.0 grams per squaremeter composition including the supersaturated solution, and a corecomposition including at least one activation means. More suitably, thewipes comprise at least about 30 grams per square meter compositionincluding supersaturated solution, and a core composition including atleast about 10 activation means, and, even more suitably, at least about100 grams per square meter composition including supersaturatedsolution, and a core composition including at least about 100 activationmeans.

In the embodiment, where the composition including the supersaturatedsolution is in a first fluid-impermeable pouch and the core compositionincluding the activation means is in a second fluid-impermeable pouch(as more fully described below), the first fluid-impermeable pouchsuitably comprises at least about 3.0 grams per square meter compositionof supersaturated solution, and the second fluid-impermeable pouchcomprises a core composition including at least one activation means.More suitably, the first fluid-impermeable pouch comprises at leastabout 30 grams per square meter composition, and the secondfluid-impermeable pouch comprises a core composition including at leastabout 10 activation means, and, even more suitably, the firstfluid-impermeable pouch comprises at least about 100 grams per squaremeter composition including supersaturated solution, and the secondfluid-impermeable pouch comprises a core composition including at leastabout 100 activation means.

In the embodiment where the supersaturated solution is in a gelledcomposition, the wipe suitably comprises at least about 3.00 grams persquare meter gelled composition, and a core composition including atleast one activation means. More suitably, the wipes comprise at leastabout 30 grams per square meter gelled composition, and a corecomposition including at least about 10 activation means, and, even moresuitably, at least about 100 grams per square meter gelled composition,and a core composition including at least about 100 activation means.

As noted above, the supersaturated solution is present in thecomposition in an amount of from about 70% (by weight composition) toabout 99.9% (by weight composition). More suitably, the supersaturatedsolution is present in the composition in an amount of from about 90%(by weight composition) to about 99.5% (by weight composition), and evenmore suitably, from about 93% (by weight composition) to about 99% (byweight composition).

The supersaturated solutions and core compositions including theactivation means can be applied to the basesheet material of a wipeusing any means known to one skilled in the art. Preferably, both thesupersaturated solution and the core composition are embedded within oneor more fluid-impermeable layers such as a film; the fluid-impermeablelayers being enclosed by one or more basesheet materials laminated tothe outside of the fluid-impermeable layers. By embedding the corecomposition within the core of a multi-layer wipe, the wipe will have areduced grittiness feel because of a cushion effect and the rupturedshells of the core composition will not come into direct contact withthe user's skin. Additionally, when the core composition is locatedbetween two or more layers, the activation means are better protectedfrom premature contact with the supersaturated solution and heat releasecaused by the conditions of manufacturing, storage, and transportationof the wipe.

Moreover, by embedding the supersaturated solution within the core ofthe multi-layer wipe, the supersaturated solution is not diluted by thewet wipe solution, and further, less evaporation of supersaturatedsolution can occur. This allows for an optimal concentration of thesupersaturated solution to warm the wipe effectively as described above.Furthermore, the supersaturated solution typically has a high solidscontent and can leave residue on the surface of a user's skin. Theresidue can cause irritation and/or an odor. As such, by embedding thesolution, there is less residue left on the skin by the supersaturatedsolution.

In one embodiment, both the supersaturated solution and the corecomposition including the activation means are entrapped between a firstfluid-impermeable layer and a second fluid-impermeable layer. While inthis embodiment the wipe suitably comprises two fluid-impermeablelayers, it should be understood that the wipe can suitably comprisethree fluid-impermeable layers, even more suitably fourfluid-impermeable layers, and even more suitably five or morefluid-impermeable layers. In one embodiment, the layers are separatelayers. In another embodiment, the layers are plied together.

Suitable fluid-impermeable include film materials such as polyethylenefilms having a thickness of from about 0.008 millimeters (0.3 mil) toabout 0.051 millimeters (2.0 mil). Other suitable film materialsinclude, for example, polyethylene, polypropylene, and polylactic acid.The film can include 48-60% (by weight) linear low density polyethyleneand 38-50% (by weight) calcium carbonate particulates that may beuniformly dispersed and extruded into the film. Another example of asuitable film can be a PMP-1 material, which is available from MitsuiToatsu Chemicals, Inc., a company having offices in Tokyo, Japan; or anXKO-8044 polyolefin film available from 3M Company of Minneapolis, Minn.Other suitable films include copolymers of polypropylene andpolyethylene, and polyester.

To incorporate the supersaturated solution and the core compositionincluding the activation means in between the layers offluid-impermeable material, the supersaturated solution and corecomposition are sandwiched between a first layer and a second layer ofthe fluid-impermeable material, and the layers are then laminatedtogether using any means known in the art. For example, the layers canbe secured together thermally or by a suitable laminating adhesivecomposition.

Thermal bonding includes continuous or discontinuous bonding using aheated roll. Point bonding is one suitable example of such a technique.Thermal bonds should also be understood to include various ultrasonic,microwave, and other bonding methods wherein the heat is generated inthe film.

In a preferred embodiment, the first layer and second layer arelaminated together using a water insoluble adhesive composition.Suitable water insoluble adhesive compositions can include hot meltadhesives and latex adhesives as described in U.S. Pat. Nos. 6,550,633,issued to Huang, et al. (Apr. 22, 2003); 6,838,154, issued to Anderson,et al. (Oct. 25, 2005); and 6,958,103, issued to Varona et al. (Jan. 4,2005), which are hereby incorporated by reference to the extent they areconsistent herewith. Suitable hot melt adhesives can include, forexample, RT 2730 APAO and RT 2715 APAO, which are amorphouspolyalphaolefin adhesives (commercially available from Huntsman PolymersCorporation, Odessa, Tex.) and H2800, H2727A, and H2525A, which are allstyrenic block copolymers (commercially available from Bostik Findley,Inc., Wauwatosa, Wis.). Suitable latex adhesives include, for example,DUR-O-SET E-200 (commercially available from National Starch andChemical Co., Ltd., Bridgewater, N.J.) and Hycar 26684 (commerciallyavailable from B. F. Goodrich, Laval, Quebec). Typically, the adhesivecomposition can be applied to the desired area by spraying, knifing,roller coating, or any other means suitable in the art for applyingadhesive compositions.

Suitably, the adhesive composition can be applied to the desired area ofthe fluid-impermeable material in an amount of from about 0.01 grams persquare meter to about 20 grams per square meter. More suitably, theadhesive composition can be applied in an amount of from about 0.05grams per square meter to about 0.5 grams per square meter.

In one embodiment, as depicted in FIGS. 2A and 2B, the supersaturatedsolution is combined with a gelling agent to form a gelled compositionas discussed herein above. Specifically, by forming a gelledcomposition, the supersaturated solution can be evenly distributedbetween the fluid-impermeable layers. Specifically, the gelledcomposition prevents the supersaturated solution from pooling in one ormore discreet areas of the wipe.

In another embodiment, as shown in FIGS. 1A and 1B, the supersaturatedsolution is absorbed into a fibrous sheet material and the corecomposition is deposited on an outer surface of the fibrous sheetmaterial prior to being entrapped between the first fluid-impermeablelayer and the second fluid-impermeable layer. Similar to the gelledcomposition embodiment, the fibrous sheet allows for an evendistribution of supersaturated solution between the fluid-impermeablelayers. The fibrous sheet material may typically be either woven ornonwoven. For example, suitable materials for use in the wipes mayinclude nonwoven fibrous sheet materials which include meltblown,coform, air-laid, bonded-carded web materials, hydroentangled materials,and combinations thereof. Such materials can be comprised of syntheticor natural fibers, or a combination thereof. Generally, the fibroussheet material will have a dry thickness of from about 0.02 mm to about0.80 mm, more suitably, from about 0.05 mm to about 0.30 mm, and evenmore suitably, from about 0.1 mm to about 0.2 mm. As used herein, “drythickness” refers to the thickness of the fibrous sheet material priorto adding the supersaturated solution and core composition.

To provide for better attachment of the core composition to the outersurface of the fibrous sheet material, a water insoluble adhesivecomposition can be applied with the core composition onto the outersurface of the fibrous sheet material. Suitable water insoluble adhesivecompositions are described herein above. Suitably, the adhesivecomposition can be applied to the outer surface of the fibrous sheetmaterial in an amount of from about 0.01 grams per square meter to about20 grams per square meter. More suitably, the adhesive composition canbe applied in an amount of from about 0.05 grams per square meter toabout 0.5 grams per square meter.

Additionally, the fibrous sheet material can be cut into variouspatterns prior to incorporating the supersaturated solution and corecomposition. By using a patterned fibrous sheet material, a targetedwarming sensation can be achieved. These patterned fibrous sheetmaterials can additionally reduce manufacturing costs as reduced amountsof supersaturated solution and core composition are required. Suitably,the fibrous sheet material can be cut into patterns including, forexample, characters, an array of separate lines, swirls, numbers, ordots of supersaturated solution or core composition. Continuouspatterns, such as stripes or separate lines that run parallel with themachine direction of the web, are particularly preferred as thesepatterns may be more process-friendly.

One or more basesheet materials are then laminated to the outsidesurfaces of the fluid-impermeable layers described above. Specifically,a first basesheet material can be laminated to the outside surface ofthe first fluid-impermeable layer and a second basesheet material can belaminated to the outside surface of the second fluid-impermeable layer.The layers can be secured together thermally or by a suitable laminatingadhesive composition as described above for laminating thefluid-impermeable layers together.

Materials suitable for the basesheet material of the wipes are well knowto those skilled in the art, and are typically made from a fibrous sheetmaterial which may be either woven or nonwoven as described above.Typically, the wipes of the present disclosure define a dry basis weightof from about 25 grams per square meter to about 120 grams per squaremeter and desirably from about 40 grams per square meter to about 90grams per square meter. As used herein, “dry basis weight” refers to theweight of the fibrous sheet material prior to incorporating thesupersaturated solution and core composition therein.

In one particular embodiment, the wipes of the present disclosurecomprise one or more coform basesheets of polymer fibers and absorbentfibers having a basis weight of from about 60 to about 80 grams persquare meter and desirably about 75 grams per square meter. Such coformbasesheets are manufactured generally as described in U.S. Pat. Nos.4,100,324, issued to Anderson, et al. (Jul. 11, 1978); 5,284,703, issuedto Everhart, et al. (Feb. 8, 1994); and 5,350,624, issued to Georger, etal. (Sep. 27, 1994), which are incorporated by reference to the extentin which they are consistent herewith. Typically, such coform basesheetscomprise a gas-formed matrix of thermoplastic polymeric meltblown fibersand cellulosic fibers. Various suitable materials may be used to providethe polymeric meltblown fibers, such as, for example, polypropylenemicrofibers. Alternatively, the polymeric meltblown fibers may beelastomeric polymer fibers, such as those provided by a polymer resin.For instance, Vistamaxx® elastic olefin copolymer resin designatedVM2380, available from ExxonMobil Corporation (Houston, Tex.) or KRATONG-2755, available from Kraton Polymers (Houston, Tex.) may be used toprovide stretchable polymeric meltblown fibers for the coformbasesheets. Other suitable polymeric materials or combinations thereofmay alternatively be utilized as known in the art.

As noted above, the coform basesheet materials additionally may comprisevarious absorbent cellulosic fibers, such as, for example, wood pulpfibers. Suitable commercially available cellulosic fibers for use in thecoform basesheets can include, for example, NF 405, which is achemically treated bleached southern softwood Kraft pulp, available fromWeyerhaeuser Co. of Federal Way (Washington); NB 416, which is ableached southern softwood Kraft pulp, available from Weyerhaeuser Co.;CR-0056, which is a fully debonded softwood pulp, available fromBowater, Inc. (Greenville, S.C.); Golden Isles 4822 debonded softwoodpulp, available from Koch Cellulose (Brunswick, Ga.); and SULPHATATE HJ,which is a chemically modified hardwood pulp, available from Rayonier,Inc. (Jesup, Ga.).

The relative percentages of the polymeric meltblown fibers andcellulosic fibers in the coform basesheet can vary over a wide rangedepending upon the desired characteristics of the wipes. For example,the coform basesheet may comprise from about 20 weight percent to about50 weight percent, desirably from about 15 weight percent to about 40weight percent, and more desirably from about 25 weight percent to about35 weight percent of the polymeric meltblown fibers based on the dryweight of the coform basesheet being used to provide the wipes.

When the basesheet material is a meltblown material, the basesheetmaterial can suitably be made up of two meltblown layers securedtogether, more suitably three meltblown layers, even more suitably fourmeltblown layers, and even more suitably five or more meltblown layers.When the basesheet material is a coform material, the basesheet materialcan suitably be made up of two coform basesheet layers secured together,more suitably three coform basesheet layers, even more suitably fourcoform basesheet layers, even more suitably five or more coformbasesheet layers.

In yet another embodiment, the supersaturated solution and corecomposition including the activation means may be independentlydistributed within one or more pouches of fluid-impermeable material andthen the pouch or pouches can be embedded within the basesheet materialas described above. It should be noted that when there is only onepouch, the supersaturated solution and core composition should remainseparated by being contained in separate compartments within the pouch.

In one preferred embodiment, as shown in FIGS. 3A and 3B, thesupersaturated solution is gelled using a gelling agent and the gelledcomposition is incorporated into a single pouch with the corecomposition including the activation means. The gelled composition andthe core composition are separated by air. In this embodiment, the corecomposition can be surrounded by petroleum jelly (or another gelatinoushydrophobic material) to gel the core composition in between the airgaps and gelled composition. In one particularly preferred embodiment,the core composition is surrounded by from about 300% (by weight corecomposition) to about 100,000% (by weight core composition) Vaseline®Petroleum Jelly.

In another preferred embodiment, as shown in FIGS. 4A and 4B, thesupersaturated solution can be incorporated into a firstfluid-impermeable pouch and the core composition including theactivation means can be incorporated into a second fluid-impermeablepouch. The pouches or compartments of a single pouch are then separatedby a sealed seam defined by thermally sealed facing regions of thefluid-impermeable material. It should be understood that the term “seal”is meant to encompass all types of pouch opening configurations,including perforated tear lines, scored lines, tear zones, etc. The sealis preferably a “frangible seal” that can be ruptured by application ofa manual compression of the pouch; thus allowing the confinedsupersaturated solution of one pouch or compartment to commingle withthe core composition of another pouch or compartment.

The fluid-impermeable pouches are comprised of the fluid-impermeablematerials such as the film materials described herein above.Specifically, to produce a fluid-impermeable pouch, thefluid-impermeable material (e.g., film) is folded at a fold axis suchthat the first end is folded towards the second end to define at least aportion of a front panel of the pouch. Once folded, the aligned lateralsides of the fluid-impermeable material define lateral edges of thepouch. Three sides of the pouch are then thermally sealed using methodssuch as a conventional heated bonding roll. The bonding parameters, suchas temperature, dwell time, etc., may be readily empirically determinedby those skilled in the art as a function of the type of film material,processing speed, desired seal strength, and so forth. Also, the bondingpattern may be any one or combination of suitable patterns.

In one embodiment, the frangible seal in between the first and secondfluid-impermeable pouches or separate compartments of onefluid-impermeable pouch can suitably be formed by heat-sealing twosuperimposed multilayer sheets of fluid-impermeable material each havingan innermost sealing layer made from a resin. Suitable resins includeblends of one or more polyolefins such as polyethylene includingmetallocene polyethylene with polybutylene or polypropylene includinghomopolymer or copolymers thereof (specifically,polyethylene/polybutylene blends and polyethylene/polypropylene blends),polypropylene with polybutylene; polypropylene with ethylene methacrylicacid copolymer, and polypropylene with styrene-ethylene/butylene-styreneblock terpolymer. For example, in one specific embodiment, one side ofthe pouch described above is superimposed and heat sealed using a resin.

In order to manufacture a frangible seal containing at least one forceconcentrating means for selectively exceeding the seal strength of thefrangible seal various methodologies are contemplated. Preferably, shapeand/or curvature of the frangible seal are to be employed toadvantageously concentrate the forces created when the pouch is manuallycompressed or squeezed. Also, the geometry and/or variable width of theheated seal employed to heat seal the frangible seal can be employed toproduce a force concentrating means useful in the present disclosure.

For purposes of measuring seal strength, 4 inch×6 inch samples of thefluid-impermeable material are to be cut with the long side of thesamples in the machine direction of the fluid-impermeable material.Enough film samples are cut to provide one set of three specimens foreach heat seal condition. The samples then are folded so that thesealant layer of each side contacts the other. The sample is then heatsealed between the jaws of the heat sealer at the appropriatetemperature, time and pressure. The heat-sealed samples are thenconditioned for at least 24 hours at 73° F. (22.8° C.) and 50% relativehumidity before testing. The folded over portion of the sealedfluid-impermeable material is cut in half, forming suitable flaps to beplaced in the Instron jaw clamps. One inch specimens are then cut in themachine direction of the fluid-impermeable material to provide at leastthree 1 inch wide test specimens at each set of sealing conditions.

The seal strength is measured by pulling the seals apart in the machinedirection of the fluid-impermeable material using the Instron at 5inches/minute jaw speed. The maximum force required to cause the seal tofail is then recorded, and the average of at least three specimens isreported in grams/inch. Suitably, the seal strength of the frangibleseal utilized is from about 10 grams/inch to about 3,000 grams/inch.

When using separate pouches or compartments within a single pouch, thesupersaturated solution can optionally be combined with a gelling agentto form a gelled composition as discussed herein above at the time of orprior to being incorporated into the pouch or compartment.

Additionally, the core composition may be colored using a coloring agentprior to applying the core composition to the wipe. The coloring of thecore composition can improve the aesthetics of the wipe. Additionally,in embodiments where targeted warming is desired, the coloring of thecore composition can direct the consumer of the wipe product to thelocation of the core composition in the wipe.

Suitable coloring agents include, for example, dyes, color additives,and pigments or lakes. Suitable dyes include, for example, Blue 1, Blue4, Brown 1, External Violet 2, External Violet 7, Green 3, Green 5,Green 8, Orange 4, Orange 5, Orange 10, Orange 11, Red 4, Red 6, Red 7,Red 17, Red 21, Red 22, Red 27, Red 28, Red 30, Red 31, Red 33, Red 34,Red 36, Red 40, Violet 2, Yellow 5, Yellow 6, Yellow 7, Yellow 8, Yellow10, Yellow 11, Acid Red 195, Anthocyanins, Beetroot Red, BromocresolGreen, Bromothymol Blue, Capsanthin/Capsorubin, Curcumin, andLactoflavin. Also, many dyes found suitable for use in the EuropeanUnion and in Japan may be suitable for use as coloring agents in thepresent disclosure.

Suitable color additives include, for example, aluminum powder, annatto,bismuth citrate, bismuth oxychloride, bronze powder, caramel, carmine,beta carotene, chloraphyllin-copper complex, chromium hydroxide green,chromium oxide greens, copper powder, disodium EDTA-copper, ferricammonium ferrocyanide, ferric ferrocyanide, guauazulene, guanine, henna,iron oxides, lead acetate, manganese violet, mica, pyrophylite, silver,titanium dioxide, ultramarines, zinc oxide, and combinations thereof.

Suitable pigments or lakes include, for example, Blue 1 Lake, ExternalYellow 7 Lake, Green 3 Lake, Orange 4 Lake, Orange 5 Lake, Orange 10Lake, Red 4 Lake, Red 6 Lake, Red 7 Lake, Red 21 Lake, Red 22 Lake, Red27 Lake, Red 28 Lake, Red 30 Lake, Red 31 Lake, Red 33 Lake, Red 36Lake, Red 40 Lake, Yellow 5 Lake, Yellow 6 Lake, Yellow 7 Lake, Yellow10 Lake, and combinations thereof.

Any means known to one of skill in the art capable of producingsufficient force to break the encapsulated core composition can be usedin the present disclosure. In one embodiment, the encapsulated corecomposition can be broken by the user at the point of dispensing thewipe from a package. For example, a mechanical device located inside ofthe package containing the wipes can produce a rupture force sufficientto rupture the capsules upon dispensing the wipe, thereby exposing thecontents (i.e., activation means) of the core composition to thesupersaturated solution.

In another embodiment, the capsules can be broken by the user just priorto or at the point of use of the wipe. By way of example, in oneembodiment, the force produced by the hands of the user of the wipe canbreak the capsules, exposing the contents of the core composition.

In one specific embodiment, a product including the supersaturatedsolution and core composition as described herein can additionallysuitably include a biocide agent for use in cleaning.

Using the supersaturated solution and core composition in the product incombination with the biocide agents results in an increased biocidaleffect when the supersaturated solution is contacted with the activationmeans and heat is generated. Specifically, the increase in temperaturehas been found to activate or enhance the function of the biocide agentspresent in the cleansing product.

Generally, the three main factors affecting the efficacy of biocideagents include: (1) mass transfer of biocide agents in the cleansingproduct to the microbe-water interface; (2) chemisorption of biocideagents to the cell wall or cell membrane of the microbes; and (3)diffusion of the activated chemisorbed biocide agent into the cell ofthe microbe. It has been found that temperature is a primary regulatorof all three factors. For example, the lipid bilayer cell membranestructure of many microbes “melts” at higher than room temperatures,allowing holes to form in the membrane structure. These holes can allowthe biocide agent to more easily diffuse through the microbe cell wallor membrane and enter the cell.

Generally, the cleansing products of the present disclosure are capableof killing or substantially inhibiting the growth of microbes.Specifically, the biocide agent of the cleansing products interfaceswith either the reproductive or metabolic pathways of the microbes tokill or inhibit the growth of the microbes.

Microbes suitably affected by the biocide agents of the cleansingproducts include viruses, bacteria, fungi, and protozoans. Viruses thatcan be affected by the biocide agents include, for example, Influenza,Parainfluenza, Rhinovirus, Human Immunodeficiency Virus, Hepatitis A,Hepatitis B, Hepatitis C, Rotavirus, Norovirus, Herpes, Coronavirus, andHanta virus. Both gram positive and gram negative bacteria are affectedby the biocide agents of the cleansing composition. Specifically,bacteria affected by the biocide agents used in the cleansingcompositions include, for example, Staphylococcus aureus, Streptococcuspneumoniae, Streptococcus pyogenes, Pseudomonas aeruginose, Klebsiellapneumoniae, Escherichia coli, Enterobacter aerogenes, Enterococcusfaecalis, Bacillus subtilis, Salmonella typhi, Mycobacteriumtuberculosis, and Acinetobacter baumannii. Fungi affected by the biocideagents include, for example, Candida albicans, Aspergillus niger, andAspergillus fumigates. Protozoans affected by the biocide agentsinclude, for example, cyclospora cayetanensis, Cryptosporidum parvum,and species of microsporidum.

Suitable biocide agents for use in the cleansing products include, forexample, isothiazolones, alkyl dimethyl ammonium chloride, triazines,2-thiocyanomethylthio benzothiazol, methylene bis thiocyanate, acrolein,dodecylguanidine hydrochloride, chlorophenols, quarternary ammoniumsalts, gluteraldehyde, dithiocarbamates, 2-mercaptobenzothiazole,para-chloro-meta-xylenol, silver, chlorohexidine, polyhexamethylenebiguanide, n-halamines, triclosan, phospholipids, alpha hydroxyl acids,2,2-dibromo-3-nitrilopropionamide, 2-bromo-2-nitro-1,3-propanediol,farnesol, iodine, bromine, hydrogen peroxide, chlorine dioxide,alcohols, ozone, botanical oils (e.g., tee tree oil and rosemary oil),botanical extracts, benzalkonium chloride, chlorine, sodiumhypochlorite, and combinations thereof.

The cleansing products of the present disclosure may also optionallycontain a variety of other components which may assist in providing thedesired cleaning properties. For example, additional components mayinclude non-antagonistic emollients, surfactants, preservatives,chelating agents, pH adjusting agents, fragrances, moisturizing agents,skin benefit agents (e.g., aloe and vitamin E), antimicrobial actives,acids, alcohols, or combinations or mixtures thereof. The products mayalso contain lotions, and/or medicaments to deliver any number ofcosmetic and/or drug ingredients to improve performance.

Typically, to manufacture the wet wipe with the biocide agent, thebiocide agent can be applied to the outer layers of the wipe or,alternatively, added to the wet wipe solution and applied to the wipe.

In another embodiment, the biocide agents can be microencapsulated in ashell material prior to being introduced into or onto the wipe.Generally, the biocide agent can be microencapsulated using any methodknown in the art. Suitable microencapsulation shell materials includecellulose-based polymeric materials (e.g., ethyl cellulose),carbohydrate-based materials (e.g., cationic starches and sugars) andmaterials derived therefrom (e.g., dextrins and cyclodextrins) as wellas other materials compatible with human tissues.

The microencapsulation shell thickness may vary depending upon thebiocide agent utilized, and is generally manufactured to allow theencapsulated formulation or component to be covered by a thin layer ofencapsulation material, which may be a monolayer or thicker laminatelayer, or may be a composite layer. The microencapsulation layer shouldbe thick enough to resist cracking or breaking of the shell duringhandling or shipping of the product. The microencapsulation layer shouldalso be constructed such that atmospheric conditions duringmanufacturing, storage, and/or shipment will not cause a breakdown ofthe microencapsulation layer and result in a release of the biocideagent.

Microencapsulated biocide agents applied to the outer surface of thewipes as discussed above should be of a size such that the user cannotfeel the encapsulated shell on the skin during use. Typically, thecapsules have a diameter of no more than about 25 micrometers, anddesirably no more than about 10 micrometers. At these sizes, there is no“gritty” or “scratchy” feeling on the skin when the wipe is utilized.

Suitably, the biocide agent is present in the wet wipe in an amount ofsuitably 0.001 grams per square meter to about 50 grams per squaremeter. More suitably, the biocide agent is present in the wet wipe in anamount of from about 0.002 grams per square meter to about 25 grams persquare meter, and even more suitably, in an amount of from about 0.002grams per square meter to about 4.0 grams per square meter.

The present disclosure is illustrated by the following examples whichare merely for the purpose of illustration and are not to be regarded aslimiting the scope of the disclosure or manner in which it may bepracticed.

EXAMPLE 1

In this example, a sample of supersaturated salt solution was evaluatedfor its ability to generate heat upon being contacted with an activationmeans.

To produce the supersaturated salt solution, about 12 grams of asolution of sodium acetate, having approximately 53% (by weight) sodiumacetate and having a temperature of 90-100° C. (194-212° F.), was pouredonto a 7.5 inch×7.0 inch sheet (basis weight of about 33 grams/meter²)of Scott® Paper toweling (available from Kimberly-Clark, Neenah, Wis.).The toweling was then placed into a Hefty Slide-Rite polyethylene bag(available from Pactiv Corporation, Lake Forest, Ill.) and the bag wasboiled for a few seconds. The bag was then allowed to cool.

Once cooled, the bag was opened and an agglomeration of seed crystals ofsodium acetate (about 1 mm in size) was placed onto the sheet oftoweling. Crystallization initiated and there was a perceived heatingeffect. The crystallization continued for approximately 40 seconds.

EXAMPLE 2

In this example, a sample of a gelled composition includingsupersaturated salt solution was evaluated for its ability to generateheat upon being contacted with an activation means.

To produce the gelled composition, 10% (by weight) fumed silica having aparticle size of about 0.014 microns, was mixed with 90% (by weight)supersaturated sodium acetate salt solution available from ProHeat®Reusable Handwarmer packs (available from Prism Enterprises, Inc., SanAntonio, Tex.). Approximately 5.0 grams of the resulting gelledcomposition were then placed into a Hefty Slide-Rite polyethylene bag(available from Pactiv Corporation, Lake Forest, Ill.).

An agglomeration of seed crystals of sodium acetate (approximately 1 mmin size) was placed against the gelled composition inside the bag.Crystallization initiated and there was a perceived heating effect. Thecrystallization continued for approximately 50 seconds, producing astiff solid crystallized product.

EXAMPLE 3

In this Example, a gelled composition including a supersaturated saltsolution was packaged with a powder of seed crystals in a pouch, whereinthe gelled composition and seed crystals were separated by air. Thepouch was squeezed manually to allow the contents of the pouch tocommingle and the ability of the supersaturated salt solution togenerate heat once contacted with the seed crystals was evaluated.

A first mixture of a gelled composition was produced by mixing 6.3% (byweight) fumed silica with 93.7% (by weight) ProHeat® sodium acetatesolution. A second mixture was formed from 10% (by weight) sodiumacetate powder and 90% (by weight) Vaseline® Petroleum Jelly.

The first mixture of gelled composition was placed into a polyethylenebag in two separate locations. The second mixture containing the seedcrystals was placed in a stripe in between the two areas containing thefirst mixture. When the polyethylene films of the bag were pinched andmoved between fingers of the tester, the first mixture contacted thesecond mixture and crystallization was initiated in multiple locations.As crystallization continued, heat was generated.

When introducing elements of the present disclosure or the preferredembodiment(s) thereof, the articles “a”, “an”, “the” and “said” areintended to mean that there are one or more of the elements. The terms“comprising”, “including” and “having” are intended to be inclusive andmean that there may be additional elements other than the listedelements.

As various changes could be made in the above constructions withoutdeparting from the scope of the disclosure, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

1-155. (canceled)
 156. A wet wipe comprising a composition comprising asupersaturated solution, and a core composition surrounded by anencapsulation layer, the core composition comprising a matrix materialand an activation means.
 157. The wet wipe as set forth in claim 156wherein the composition is present in the wet wipe in an amount of fromabout 3.0 grams per square meter to about 850 grams per square meter.158. The wet wipe as set forth in claim 156 wherein the supersaturatedsolution is a supersaturated salt solution prepared from an aqueoussolution of a salt, the salt being selected from the group consisting ofsodium acetate, sodium sulfate, sodium thiosulfate, potash alum, calciumnitrate, potassium acetate, ammonium nitrate, potassium nitrate, lithiumacetate, magnesium acetate, chromium alum, sodium carbonate, magnesiumsulfate, sodium borate, sodium bromide, sodium chromate, calciumchloride, magnesium chloride, magnesium nitrate, disodium phosphate,urea nitrate, and hydrates thereof.
 159. The wet wipe as set forth inclaim 156 wherein the supersaturated solution is a supersaturated sugarsolution prepared from an aqueous solution of a sugar, the sugar beingxylitol.
 160. The wet wipe as set forth in claim 156 wherein thesupersaturated solution is present in the composition in an amount offrom about 70% (by weight) to about 99.9% (by weight).
 161. The wet wipeas set forth in claim 156 wherein the composition further comprises aplasticizer.
 162. The wet wipe as set forth in claim 161 wherein thecomposition further comprises an emulsifying agent in combination withthe plasticizer.
 163. The wet wipe as set forth in claim 156 wherein theactivation means is selected from the group consisting of sodiumacetate, sodium sulfate, sodium sulfate decahydrate, sodium thiosulfate,potash alum, calcium nitrate, potassium acetate, ammonium nitrate,potassium nitrate, lithium acetate, magnesium acetate, chromium alum,sodium carbonate, magnesium sulfate, sodium borate, sodium bromide,xylitol, sodium chromate, calcium chloride, magnesium chloride,magnesium nitrate, disodium phosphate, urea nitrate, and hydratesthereof.
 164. The wet wipe as set forth in claim 156 wherein theactivation means is present in the core composition in an amount of fromabout 0.1% (by weight core composition) to about 80% (by weight corecomposition)
 165. The wet wipe as set forth in claim 156 furthercomprising a moisture protective layer surrounding the encapsulationlayer.
 166. The wet wipe as set forth in claim 165 further comprising afugitive layer surrounding the moisture protective layer.
 167. The wetwipe as set forth in claim 156 wherein upon contact between thesupersaturated solution and the activation means, the temperature of thewet wipe is increased by at least about 5° C. in less than about 20seconds.
 168. The wet wipe as set forth in claim 167 wherein theincreased temperature of the wet wipe is maintained for at least about 5seconds.
 169. The wet wipe as set forth in claim 156 wherein thecomposition is a gelled composition and the gelled composition comprisesa gelling agent in combination with the supersaturated solution. 170.The wet wipe as set forth in claim 169 wherein the gelled composition ispresent in the wet wipe in an amount of from about 3.0 grams per squaremeter to about 850 grams per square meter.
 171. The wet wipe as setforth in claim 169 wherein the gelling agent is selected from the groupconsisting of fumed silica and laponite clay.
 172. The wet wipe as setforth in claim 156 further comprising a first fluid-impermeable pouchand a second fluid-impermeable pouch, wherein the firstfluid-impermeable pouch comprises the composition comprising thesupersaturated solution and the second fluid-impermeable pouch comprisesthe core composition comprising the matrix material and activationmeans.
 173. The wet wipe as set forth in claim 172 wherein the firstfluid-impermeable pouch and second fluid-impermeable pouch are connectedby a frangible seal.
 174. The wet wipe as set forth in claim 156 furthercomprising a fibrous sheet material, the fibrous sheet materialcomprising the composition comprising the supersaturated solution. 175.A method of producing a wipe comprising: encapsulating an activationmeans within a core composition; and incorporating a compositioncomprising a supersaturated solution, and the core composition within abasesheet material.